Chronic obstructive pulmonary disease (COPD) is a type of obstructive lung disease characterized by long-term poor airflow. The main symptoms include shortness of breath and cough with sputum production. COPD typically worsens over time. Eventually walking up stairs or carrying things will be difficult. Chronic bronchitis and emphysema are older terms used for different types of COPD.[2][3] The term "chronic bronchitis" is still used to define a productive cough that is present for at least three months each year for two years